Sussex Tech teacher accused of sexual assault

A math teacher at the Sussex County Technical School in Sparta has been arrested for allegedly having sexual contact with two students, the Sussex County Prosecutor's Office announced today.

Richard Koppenaal, 37, of Frankford, was arrested Friday at the school after the school day had ended, and has been charged with one count of second-degree sexual assault and three counts of fourth-degree criminal sexual contact, authorities said.

Koppenaal is accused of having sexual contact with two students from the school between October 2006 and October 2007 and of committing acts of sexual assault involving penetration with one of his students in September and October 2007, the prosecutor's office said.

Koppenaal has been suspended from his $52,593-a-year job, said Tech school Superintendent Mark Toback. He has worked at the school for four years.

Koppenaal earned another $14,500 a year in various stipends for other services that he performed, including student council adviser, sophomore class co-adviser, after-school parking lot supervisor and teacher leader in analyzing test scores, Toback said.

The school told students and staff about the arrest this morning, and had counselors available, he said.

"It's very difficult for all involved," Toback said.

Koppenaal is being held in the county jail. His bail was set at $100,000 bail. He must post the full amount before he will be released.